Stock-based Compensation Expense Stock Based Compensation Expense (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Oct. 31, 2015	Oct. 31, 2014	Oct. 31, 2015	Oct. 31, 2014
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation expense related to stock awards and ESPP purchases	$ 50.2	$ 43.1	$ 141.1	$ 116.5
Tax benefit	0.0	(11.7)	0.0	(31.3)
Stock-based compensation expense related to stock awards and ESPP purchases, net of tax	50.2	31.4	141.1	85.2
Cost of license and other revenue
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Allocated share-based compensation expense	1.7	1.2	4.4	3.2
Cost of subscription
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Allocated share-based compensation expense	1.5	1.1	4.1	2.9
Marketing and sales
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Allocated share-based compensation expense	22.3	19.4	61.3	51.0
Research and development
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Allocated share-based compensation expense	17.5	14.7	49.9	39.3
General and administrative
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Allocated share-based compensation expense	$ 7.2	$ 6.7	$ 21.4	$ 20.1